2-1.3 Dimensions and Shape

Each machinable or automation letter-size piece must be rectangular and must meet the following standards (see chapter 4 for booklets and folded self-mailers):

1. For length, no more than 11-1/2" or less than 5".
2. For height, no more than 6-1/8" or less than 3-1/2".
3. For thickness, no more than 1/4" or less than either of the following:
1. 0.007" thick if no more than 6" long and 4-1/4" high.
2. 0.009" thick if either more than 6" long or 4-1/4" high, or both.